Open Access. Powered by Scholars. Published by Universities.®
- Institution
-
- Selected Works (144)
- Old Dominion University (123)
- University of Massachusetts Amherst (121)
- Chapman University (80)
- Wayne State University (64)
-
- The Texas Medical Center Library (56)
- University of Kentucky (56)
- University of Tennessee, Knoxville (56)
- Western University (51)
- City University of New York (CUNY) (39)
- University of Arkansas, Fayetteville (39)
- University of Nebraska Medical Center (34)
- University of Richmond (32)
- East Tennessee State University (28)
- Technological University Dublin (28)
- Louisiana State University (27)
- Florida International University (24)
- San Jose State University (22)
- Virginia Commonwealth University (22)
- Purdue University (20)
- The University of Maine (20)
- University of Louisville (20)
- Thomas Jefferson University (18)
- Touro College and University System (17)
- SelectedWorks (16)
- Washington University in St. Louis (16)
- University of Missouri, St. Louis (15)
- University of Nevada, Las Vegas (15)
- University of South Florida (15)
- Wilfrid Laurier University (15)
- Keyword
-
- Biochemistry (59)
- Cancer (28)
- Protein (25)
- DNA (24)
- Humans (22)
-
- Biological sciences (20)
- RNA (20)
- Translation (20)
- Animals (19)
- Pure sciences (19)
- Electroporation (18)
- Biological Sciences (17)
- MicroRNAs (17)
- Molecular biology (17)
- Transcription (17)
- Apoptosis (16)
- Phosphorylation (16)
- Publications (16)
- Bioinformatics (15)
- Mutation (15)
- Drosophila (14)
- Mass spectrometry (14)
- Mice (14)
- Proteomics (14)
- Epigenetics (13)
- Mitochondria (13)
- Articles (12)
- Caenorhabditis elegans (12)
- DNA repair (12)
- Genetics (12)
- Publication Year
- Publication
-
- Biology, Chemistry, and Environmental Sciences Faculty Articles and Research (76)
- Electronic Theses and Dissertations (68)
- Dissertations & Theses (Open Access) (56)
- Doctoral Dissertations (54)
- Electronic Thesis and Dissertation Repository (50)
-
- Honors Theses (44)
- Celia A. Schiffer (38)
- Bioelectrics Publications (34)
- Theses & Dissertations (34)
- Graduate Theses and Dissertations (32)
- Theses and Dissertations (29)
- Biochemistry and Molecular Biology Faculty Publications (27)
- Dissertations, Theses, and Capstone Projects (27)
- Masters Theses (26)
- Articles (25)
- FIU Electronic Theses and Dissertations (23)
- Victor R. Ambros (22)
- Wayne State University Dissertations (21)
- Chemistry & Biochemistry Theses & Dissertations (19)
- Theses and Dissertations--Molecular and Cellular Biochemistry (18)
- NYMC Faculty Publications (17)
- Theses and Dissertations in Biomedical Sciences (17)
- Faculty Publications (16)
- Chancellor’s Honors Program Projects (15)
- USF Tampa Graduate Theses and Dissertations (15)
- Arts & Sciences Electronic Theses and Dissertations (14)
- Department of Biochemistry and Molecular Biology Faculty Papers (14)
- LSU Doctoral Dissertations (14)
- Pr. Mamoudou H. DICKO, PhD (14)
- Wayne State University Theses (14)
- Publication Type
Articles 1 - 30 of 1658
Full-Text Articles in Molecular Biology
Purification Of Recombinant E. Coli Topoisomerase Iii For Structure-Based Drug Design Using Protein Crystallization, Miguel A. Perez Rodriguez, Yuk-Ching Tse-Dinh
Purification Of Recombinant E. Coli Topoisomerase Iii For Structure-Based Drug Design Using Protein Crystallization, Miguel A. Perez Rodriguez, Yuk-Ching Tse-Dinh
FIU Undergraduate Research Journal
Type IA Topoisomerases are ubiquitous enzymes found throughout all life forms and species. These topoisomerases relieve the topographical constrains formed by DNA during processes like replication and transcription via a cleavage-religation mechanism performed through a catalytically active tyrosine residue in the primary structure of the enzyme. E. coli Topoisomerase III (EtopIII) is a type of Type IA topoisomerase, and its main function in the cell is as a decatenase, which means that it unlinks circular or intertwined pieces of genetic material and creates two unlinked segments of DNA from a singular linked chain. Structure-based determination of the enzyme’s three-dimensional structure …
A Review Of Rheb Activation Of Mtorc1 And The Great Mystery Of One Missing Gef, Jack Gregory
A Review Of Rheb Activation Of Mtorc1 And The Great Mystery Of One Missing Gef, Jack Gregory
Senior Honors Theses
The mTORC1 pathway is involved in the regulation of cell growth and translation. The pathway has a complex web of activators and inhibitors to activate mTORC1. mTORC1 is regulated via a small GTPase called Rheb, which interacts directly with mTORC1. This GTPase and its GTPase activating protein (GAP), TSC1/2, have been widely studied to understand how the variety of regulators of mTORC1 interact with these proteins. Despite this, the guanine nucleotide exchange factor (GEF) of Rheb has yet to be identified. This review broadly analyzes Rheb and mTORC1, their structures, regulations, and interactions, and explores the mystery of the missing …
Discovery Of A Small-Molecule Inhibitor That Traps Polθ On Dna And Synergizes With Parp Inhibitors, William Fried, Mrityunjay Tyagi, Leonid Minakhin, Gurushankar Chandramouly, Taylor Tredinnick, Mercy Ramanjulu, William Auerbacher, Marissa L Calbert, Timur Rusanov, Trung Hoang, Nikita Borisonnik, Robert Betsch, John Krais, Yifan Wang, Umeshkumar Vekariya, John Gordon, George Morton, Tatiana Kent, Tomasz Skorski, Neil Johnson, Wayne Childers, Xiaojiang Chen, Richard Pomerantz
Discovery Of A Small-Molecule Inhibitor That Traps Polθ On Dna And Synergizes With Parp Inhibitors, William Fried, Mrityunjay Tyagi, Leonid Minakhin, Gurushankar Chandramouly, Taylor Tredinnick, Mercy Ramanjulu, William Auerbacher, Marissa L Calbert, Timur Rusanov, Trung Hoang, Nikita Borisonnik, Robert Betsch, John Krais, Yifan Wang, Umeshkumar Vekariya, John Gordon, George Morton, Tatiana Kent, Tomasz Skorski, Neil Johnson, Wayne Childers, Xiaojiang Chen, Richard Pomerantz
Department of Biochemistry and Molecular Biology Faculty Papers
The DNA damage response (DDR) protein DNA Polymerase θ (Polθ) is synthetic lethal with homologous recombination (HR) factors and is therefore a promising drug target in BRCA1/2 mutant cancers. We discover an allosteric Polθ inhibitor (Polθi) class with 4-6 nM IC50 that selectively kills HR-deficient cells and acts synergistically with PARP inhibitors (PARPi) in multiple genetic backgrounds. X-ray crystallography and biochemistry reveal that Polθi selectively inhibits Polθ polymerase (Polθ-pol) in the closed conformation on B-form DNA/DNA via an induced fit mechanism. In contrast, Polθi fails to inhibit Polθ-pol catalytic activity on A-form DNA/RNA in which the enzyme binds in …
The Impact Of Mutations In The Arabidopsis Apetela (Ap3) Gene, Hazel R. Frans, Tara Phelps-Durr
The Impact Of Mutations In The Arabidopsis Apetela (Ap3) Gene, Hazel R. Frans, Tara Phelps-Durr
SACAD: John Heinrichs Scholarly and Creative Activity Days
The purpose of this research is to understand the molecular functioning of the Arabidopsis thaliana Apetela (Ap3) gene. We created mutations in two sites of the gene, AP3-3 and AP3-5. These are predicted to change AP3 protein structure, which may result in a mutated flower. Analyzing the effects of new mutations allows an understanding of protein formation both in plants and humans.
Parp2 Promotes Break Induced Replication-Mediated Telomere Fragility In Response To Replication Stress, Daniela Muoio, Natalie Laspata, Rachel L Dannenberg, Caroline Curry, Simone Darkoa-Larbi, Mark Hedglin, Shikhar Uttam, Elise Fouquerel
Parp2 Promotes Break Induced Replication-Mediated Telomere Fragility In Response To Replication Stress, Daniela Muoio, Natalie Laspata, Rachel L Dannenberg, Caroline Curry, Simone Darkoa-Larbi, Mark Hedglin, Shikhar Uttam, Elise Fouquerel
Department of Biochemistry and Molecular Biology Faculty Papers
PARP2 is a DNA-dependent ADP-ribosyl transferase (ARTs) enzyme with Poly(ADP-ribosyl)ation activity that is triggered by DNA breaks. It plays a role in the Base Excision Repair pathway, where it has overlapping functions with PARP1. However, additional roles for PARP2 have emerged in the response of cells to replication stress. In this study, we demonstrate that PARP2 promotes replication stress-induced telomere fragility and prevents telomere loss following chronic induction of oxidative DNA lesions and BLM helicase depletion. Telomere fragility results from the activity of the break-induced replication pathway (BIR). During this process, PARP2 promotes DNA end resection, strand invasion and BIR-dependent …
A Comparison Of In Vitro Studies Between Cobalt(Iii) And Copper(Ii) Complexes With Thiosemicarbazone Ligands To Treat Triple Negative Breast Cancer, Duaa R. Alajroush, Chloe B. Smith, Brittney F. Anderson, Ifeoluwa T. Oyeyemi, Stephen J. Beebe, Alvin A. Holder
A Comparison Of In Vitro Studies Between Cobalt(Iii) And Copper(Ii) Complexes With Thiosemicarbazone Ligands To Treat Triple Negative Breast Cancer, Duaa R. Alajroush, Chloe B. Smith, Brittney F. Anderson, Ifeoluwa T. Oyeyemi, Stephen J. Beebe, Alvin A. Holder
Undergraduate Research Symposium
Triple negative breast cancer (TNBC) is one of the most aggressive forms of breast cancer, and disproportionately affects African American women. TNBC cells lack the common hormone receptors that many pre-existing cancer treatments target. Fortunately, metal-based complexes with thiosemicarbazone ligands have gained significant attention for their potential as anti-cancer agents. Cobalt(III) complex ([Co(phen)2(MeATSC)](NO3)3•1.5H2O•C2H5OH]) and Copper(II) complex ([Cu(acetylethTSC)Cl]Cl•0.25C2H5OH) specifically have properties of high toxicity, which can contribute to decreased cancer cell activity. The effects of these complexes are currently being investigated on cancerous and non-cancerous breast cell lines. The cytotoxic effect of the cobalt(lll) complex and the copper(ll) complex was analyzed …
In Silico Analysis Of C-Type Lectins As Co-Infection Receptors Of Dengue And Chikungunya Viruses In Aedes Aegypti, Munawir Sazali, R. C. Hidayat Soesilohadi, Nastiti Wijayanti, Tri Wibawa, Arif Nur Muhammad Ansori
In Silico Analysis Of C-Type Lectins As Co-Infection Receptors Of Dengue And Chikungunya Viruses In Aedes Aegypti, Munawir Sazali, R. C. Hidayat Soesilohadi, Nastiti Wijayanti, Tri Wibawa, Arif Nur Muhammad Ansori
Makara Journal of Science
Aedes aegypti is a primer vector of dengue virus (DENV) and chikungunya virus (CHIKV). The susceptibility of mosquitoes to DENV and CHIKV depends on their recognition receptor of pathogens. C-type lectins (CTLs) are an important mediator of virus infection in A. aegypti. This study aims to identify potential receptors and determine the binding affinity between ligand–receptor interaction, CTLs and virus envelopes (DENV-1, 2, 3, and 4 and CHIKV) interaction based on in silico analysis. Sample sequences were obtained from GenBank (NCBI), and 10 CTLs were acquired from VectorBase. Homology modeling based on a minimum standard of 20% was processed …
Two Dot1 Enzymes Cooperatively Mediate Efficient Ubiquitin-Independent Histone H3 Lysine 76 Tri-Methylation In Kinetoplastids, Victoria Frisbie, Hideharu Hashimoto, Yixuan Xie, Francisca De Luna Vitorino, Josue Baeza, Tam Nguyen, Zhangerjiao Yuan, Janna Kiselar, Benjamin Garcia, Erik Debler
Two Dot1 Enzymes Cooperatively Mediate Efficient Ubiquitin-Independent Histone H3 Lysine 76 Tri-Methylation In Kinetoplastids, Victoria Frisbie, Hideharu Hashimoto, Yixuan Xie, Francisca De Luna Vitorino, Josue Baeza, Tam Nguyen, Zhangerjiao Yuan, Janna Kiselar, Benjamin Garcia, Erik Debler
Department of Biochemistry and Molecular Biology Faculty Papers
In higher eukaryotes, a single DOT1 histone H3 lysine 79 (H3K79) methyltransferase processively produces H3K79me2/me3 through histone H2B mono-ubiquitin interaction, while the kinetoplastid Trypanosoma brucei di-methyltransferase DOT1A and tri-methyltransferase DOT1B efficiently methylate the homologous H3K76 without H2B mono-ubiquitination. Based on structural and biochemical analyses of DOT1A, we identify key residues in the methyltransferase motifs VI and X for efficient ubiquitin-independent H3K76 methylation in kinetoplastids. Substitution of a basic to an acidic residue within motif VI (Gx6K) is essential to stabilize the DOT1A enzyme-substrate complex, while substitution of the motif X sequence VYGE by CAKS renders a rigid active-site …
Differentially Disrupted Spinal Cord And Muscle Energy Metabolism In Spinal And Bulbar Muscular Atrophy, Danielle Debartolo, Frederick Arnold, Y Liu, Elana Molotsky, Hsin-Yao Tang, Diane Merry
Differentially Disrupted Spinal Cord And Muscle Energy Metabolism In Spinal And Bulbar Muscular Atrophy, Danielle Debartolo, Frederick Arnold, Y Liu, Elana Molotsky, Hsin-Yao Tang, Diane Merry
Department of Biochemistry and Molecular Biology Faculty Papers
Prior studies showed that polyglutamine-expanded androgen receptor (AR) is aberrantly acetylated and that deacetylation of the mutant AR by overexpression of nicotinamide adenine dinucleotide-dependent (NAD+-dependent) sirtuin 1 is protective in cell models of spinal and bulbar muscular atrophy (SBMA). Based on these observations and reduced NAD+ in muscles of SBMA mouse models, we tested the therapeutic potential of NAD+ restoration in vivo by treating postsymptomatic transgenic SBMA mice with the NAD+ precursor nicotinamide riboside (NR). NR supplementation failed to alter disease progression and had no effect on increasing NAD+ or ATP content in muscle, despite producing a modest increase of …
Long Non-Coding Rna As A Potential Diagnostic Tool In Coronary Artery Diseases - A Systematic Review, Arthi Sri A.S, Vishnu Priya Veeraraghavan
Long Non-Coding Rna As A Potential Diagnostic Tool In Coronary Artery Diseases - A Systematic Review, Arthi Sri A.S, Vishnu Priya Veeraraghavan
Annual Research Symposium
POSTER - SYSTEMATIC REVIEW - LONG NON CODING RNAS AS DIAGNOSTIC MARKER FOR CAD
Correlation Between Salivary Levels And Tissue Expression Status Of Her2 In Breast Cancer Patients - A Cross-Sectional Study, Arthi Sri A.S, Massillamani F, Vinothkumar Thilla Sekar
Correlation Between Salivary Levels And Tissue Expression Status Of Her2 In Breast Cancer Patients - A Cross-Sectional Study, Arthi Sri A.S, Massillamani F, Vinothkumar Thilla Sekar
Annual Research Symposium
The study aims to investigate if soluble salivary human epidermal growth factor receptor-2 (HER2) would play a role in the diagnosis of breast cancer patients and also to find out the influence of demographic and hormonal factors on the salivary HER2 levels in breast cancer.
Studying The Genes And Conditions That Influence Root Development, Tessa Holtkamp, Hannah Ordonez Webb
Studying The Genes And Conditions That Influence Root Development, Tessa Holtkamp, Hannah Ordonez Webb
Undergraduate Research Symposium
Root development in plants is essential for their survival and understanding how hormones influence their development can explain how plants grow under different circumstances. Researching how Indole-3-butyric acid (IBA), a hormone that induces root production, affects the plant model Arabidopsis thaliana helps explain the hormone's effect in agricultural crop systems. To understand root pathways, we performed assays on mutant lines of Arabidopsis by growing plants on varying concentrations of IBA. For wild-type and mutant lines, phenotyping experiments like branching of roots, lengths of stems, and root length were conducted along with PCR and restriction digest genotyping experiments to compare their …
Identification Of Regulatory Elements In The Untranslated Regions Of Streptolysin S Associated Gene A Messenger Rna From Group A Streptococcus, Cameron R. Carroll, Sara G. Nibar, Alexis S. Brown, Lauren R. Angello, Gabriela C. Pérez-Alvarado, Brian M. Lee
Identification Of Regulatory Elements In The Untranslated Regions Of Streptolysin S Associated Gene A Messenger Rna From Group A Streptococcus, Cameron R. Carroll, Sara G. Nibar, Alexis S. Brown, Lauren R. Angello, Gabriela C. Pérez-Alvarado, Brian M. Lee
Journal of the South Carolina Academy of Science
Streptococcus pyogenes, also known as group A Streptococcus (GAS), is a human pathogen associated with a variety of diseases such as strep throat, scarlet fever, toxic shock syndrome, and necrotizing fasciitis. One of the virulence factors released by GAS during an invasive infection is a cytotoxic peptide, streptolysin S (SLS), which inhibits the immune response to necrotizing fasciitis. The streptolysin S associated gene A product, SagA, is modified to produce SLS. Thesag operon includes sagA and the genes required for enzyme-mediated post-translational modifications of SagA and the export of SLS. The sagA gene is contained within the pleiotropic …
Tail-Tape-Fused Virion And Non-Virion Rna Polymerases Of A Thermophilic Virus With An Extremely Long Tail, Anastasiia Chaban, Leonid Minakhin, Ekaterina Goldobina, Brain Bae, Yue Hao, Sergei Borukhov, Leena Putzeys, Maarten Boon, Florian Kabinger, Rob Lavigne, Kira Makarova, Eugene V Koonin, Satish Nair, Shunsuke Tagami, Konstantin Severinov, Maria Sokolova
Tail-Tape-Fused Virion And Non-Virion Rna Polymerases Of A Thermophilic Virus With An Extremely Long Tail, Anastasiia Chaban, Leonid Minakhin, Ekaterina Goldobina, Brain Bae, Yue Hao, Sergei Borukhov, Leena Putzeys, Maarten Boon, Florian Kabinger, Rob Lavigne, Kira Makarova, Eugene V Koonin, Satish Nair, Shunsuke Tagami, Konstantin Severinov, Maria Sokolova
Department of Biochemistry and Molecular Biology Faculty Papers
Thermus thermophilus bacteriophage P23-45 encodes a giant 5,002-residue tail tape measure protein (TMP) that defines the length of its extraordinarily long tail. Here, we show that the N-terminal portion of P23-45 TMP is an unusual RNA polymerase (RNAP) homologous to cellular RNAPs. The TMP-fused virion RNAP transcribes pre-early phage genes, including a gene that encodes another, non-virion RNAP, that transcribes early and some middle phage genes. We report the crystal structures of both P23-45 RNAPs. The non-virion RNAP has a crab-claw-like architecture. By contrast, the virion RNAP adopts a unique flat structure without a clamp. Structure and sequence comparisons of …
Structural Phylogenetics Of A Family Dna Polymerases, Yagmur Bingul
Structural Phylogenetics Of A Family Dna Polymerases, Yagmur Bingul
Honors Theses
The transition from the RNA to the DNA world stands as an important event, demanding the emergence of enzymatic activities for DNA precursor synthesis, retro-transcription of RNA templates, and replication of single and double-stranded DNA molecules. The distribution of protein families associated with these activities across the three domains of life—Archaea, Eukarya, and Bacteria—adds layers of complexity to the narrative. While Archaea and Eukarya often share similar protein structures, structural biology shows homologous, but distinct, structures in Bacteria. On the other hand, viral polymerases emerge as a crucial part of genome replication and transcription. Their versatility, including RNA-dependent RNA polymerase, …
Heterocycles As Peptide-Based Cleavable Linkers, John Blobe
Heterocycles As Peptide-Based Cleavable Linkers, John Blobe
Honors Theses
As cancer cases continue to rise, the need for advancing the treatment options for cancer is ever increasing. Current cancer therapeutics, while effective at treating localized cancers and a fraction of advanced cancers, generally lack the specificity needed to target more advanced cancers. Recent advancements in cancer treatments have leveraged antibodies to target certain cancers. A class of drugs that utilize antibodies to deliver anti-cancer therapy preferentially to cancer cells, termed antibody-drug conjugates (ADCs), have been quite effective in treating certain advanced forms of certain cancers. These ADCs could be more effective if they could allow for the facile release …
Functionalized Gold Nanoparticles And Halogen Bond Interactions With Neonicotinoid Pesticides, Molly Mccuen “Mackey” Sherard
Functionalized Gold Nanoparticles And Halogen Bond Interactions With Neonicotinoid Pesticides, Molly Mccuen “Mackey” Sherard
Honors Theses
Neonicotinoid (NN) pesticides have emerged globally as one of the most widely used agricultural tools for protecting crops from pest damage and boosting food production. Unfortunately, some NN compounds, such as extensively employed imidacloprid-based pesticides, have also been identified as likely endangering critical pollinating insects like honey bees. To this end, NN pesticides pose a potential threat to world food supplies. As more countries restrict or prohibit the use of NN pesticides, tools are needed to effectively and quickly identify the presence of NN compounds like imidacloprid on site (e.g., in storage areas on farms or pesticide distribution warehouses). This …
Cd46 Isoforms And Viral Receptor For Adenovirus Type 64d, Corina Stasiak
Cd46 Isoforms And Viral Receptor For Adenovirus Type 64d, Corina Stasiak
Honors Theses
Adenovirus Type 64 (Ad.64) belongs to the adenovirus subgroup D, which causes epidemic keratoconjunctivitis (EKC), otherwise known as viral pink eye. There is currently no known effective treatment for EKC. Membrane Cofactor Protein (CD46) is an integral membrane glycoprotein that, in previous studies, has been identified as a protein receptor for the closely related Ad.37. It has been determined that Ad.64 uses CD46 as a receptor on the cell surface in HeLa cells. CD46 is alternatively spliced when expressed to have different isoforms of interest, including the BC and C isoforms. Certain cell types, like A549 lung carcinoma cells, express …
Cd46 Is A Protein Receptor For Human Adenovirus Type 64, Alexander Michael Robertson
Cd46 Is A Protein Receptor For Human Adenovirus Type 64, Alexander Michael Robertson
Honors Theses
Adenoviruses are important gene delivery vectors and causative agents for a variety of human diseases such as the common cold and gastrointestinal infections. Human adenovirus type 64 (Ad64; formerly 19c) and type 37 are associated with epidemic keratoconjunctivitis. Based upon its high homology and similar disease tropism to Ad37, we hypothesized that Ad64 would have the same protein receptor, CD46 (membrane cofactor protein), as Ad37. We show that a recombinant Ad64 containing an enhanced Green Fluorescent Protein transgene (Ad64.eGFP) enters Chinese hamster ovary cells expressing human CD46 (CHO-CD46) on the surface. Entry into human cervical carcinoma (HeLa) cells is increased …
Development Of A Diaryl Oxazole-Based Cleavable Linker For Peptides, Evan Wolff
Development Of A Diaryl Oxazole-Based Cleavable Linker For Peptides, Evan Wolff
Honors Theses
The development of new cleavable linkers increases the diversity of compatible conditions for peptide discovery platforms. Potential applications for these linkers include high-throughput pharmaceutical candidate screening when utilized in Peptide Encoded Libraries (PELs). This thesis describes the development of a bifunctional diaryl oxazole-based cleavable linker that may be incorporated into compounds through Solid-Phase Peptide Synthesis (SPPS). This oxazole-based linker may be rapidly cleaved by cerium ammonium nitrate in aqueous conditions and is compatible with most natural amino acids and a variety of unnatural amino acids. This linker represents the first single-electron oxidant labile linker described to our knowledge and it …
Structural Basis For Dna Proofreading, Gina Buchel, Ashok Nayak, Karl Herbine, Azadeh Sarfallah, Viktoriia Sokolova, Angelica Zamudio-Ochoa, Dmitry Temiakov
Structural Basis For Dna Proofreading, Gina Buchel, Ashok Nayak, Karl Herbine, Azadeh Sarfallah, Viktoriia Sokolova, Angelica Zamudio-Ochoa, Dmitry Temiakov
Department of Biochemistry and Molecular Biology Faculty Papers
DNA polymerase (DNAP) can correct errors in DNA during replication by proofreading, a process critical for cell viability. However, the mechanism by which an erroneously incorporated base translocates from the polymerase to the exonuclease site and the corrected DNA terminus returns has remained elusive. Here, we present an ensemble of nine high-resolution structures representing human mitochondrial DNA polymerase Gamma, Polγ, captured during consecutive proofreading steps. The structures reveal key events, including mismatched base recognition, its dissociation from the polymerase site, forward translocation of DNAP, alterations in DNA trajectory, repositioning and refolding of elements for primer separation, DNAP backtracking, and displacement …
Developing Regulated Crispr Systems To Control Bacterial Microbiomes, Gregory M. Pellegrino
Developing Regulated Crispr Systems To Control Bacterial Microbiomes, Gregory M. Pellegrino
Electronic Thesis and Dissertation Repository
Changes to the human microbiome’s composition and metabolome are associated with numerous diseases and alterations to xenobiotic metabolism. As such, targeting the human microbiome is an increasingly popular option for therapeutic interventions. However, traditional therapies that target the microbiome such as antibiotics lack specificity, which can affect the beneficial species of the microbiome and cause adverse health outcomes such as the rise of antimicrobial-resistant bacteria. Therefore, the research and development of specific, targeted antimicrobial therapies is crucial to effectively treating microbiome dysbioses.
CRISPR and CRISPRi provide easily modifiable, RNA-guided mechanisms mediated by the Cas9 or dCas9 enzymes to induce sequence-specific …
On The Anti-Adipogenic Function Of Collagen Triple Helix Repeat-Containing Protein 1, Matthew E. Siviski
On The Anti-Adipogenic Function Of Collagen Triple Helix Repeat-Containing Protein 1, Matthew E. Siviski
Electronic Theses and Dissertations
Adipogenesis is regulated by the coordinated activity of adipogenic transcription factors, including PPAR-gamma (PPARG) and C/EBP alpha (CEBPA). Thus, dysregulated adipogenesis predisposes adipose tissues to adipocyte hypertrophy and hyperplasia. We have previously reported that mice possessing a homozygous null gene mutation in collagen triple helix repeat-containing protein 1 (CTHRC1) have increased adiposity compared to wildtype mice, supporting the concept that CTHRC1 regulates body composition. Herein, we investigated the anti-adipogenic activity of CTHRC1. Using 3T3-L1 preadipocytes, we showed significantly reduced adipogenic differentiation in the presence of CTHRC1 commensurate to marked suppression of Cebpa and Pparg gene expression. In addition, CTHRC1 increased …
Diaryl Oxazoles As Cleavable Linkers For Drug Discovery Platforms, Elizabeth Taggart
Diaryl Oxazoles As Cleavable Linkers For Drug Discovery Platforms, Elizabeth Taggart
Honors Theses
Within the field of medicine and pharmacology, discovering small molecule or biologic based molecules with therapeutic potential is a difficult task. Current methods involve individually screening hundreds of compounds on a potential target biomolecule, and recent technologies have explored peptide encoded libraries (PELs) as a means of making this screening process more high-throughput. These libraries produce a large number of small molecule drug candidates each conjugated to a unique peptide fragment, functioning as a barcode. Analysis of PELs requires the capture of hit small molecules and the subsequent release of their peptide tags; however, current approaches are limited in their …
Flavonol Glucosylation: A Structural Investigation Of The Flavonol Specific 3-O Glucosyltransferase Cp3gt, Aaron S. Birchfield
Flavonol Glucosylation: A Structural Investigation Of The Flavonol Specific 3-O Glucosyltransferase Cp3gt, Aaron S. Birchfield
Electronic Theses and Dissertations
Flavonoid glycosyltransferases (GTs), enzymes integral to plant ecological responses and human pharmacology, necessitate rigorous structural elucidation to decipher their mechanistic function and substrate specificity, particularly given their role in the biotransformation of diverse pharmacological agents and natural products. This investigation delved into a comprehensive exploration of the flavonol 3-O GT from Citrus paradisi (Cp3GT), scrutinizing the impact of a c-terminal c-myc/6x histidine tag on its enzymatic activity and substrate specificity, and successfully achieving its purification to apparent homogeneity. This established a strong foundation for potential future crystallographic and other structure/function analyses. Through the strategic implementation of site-directed mutagenesis, a thrombin …
The Identification Of Small Molecule Inhibitors To Candida Albicans Phosphatidylserine Synthase, Yue Zhou
The Identification Of Small Molecule Inhibitors To Candida Albicans Phosphatidylserine Synthase, Yue Zhou
Doctoral Dissertations
Candida albicans phosphatidylserine (PS) synthase, encoded by the CHO1 gene, has been identified as a potential drug target for new antifungals against systemic candidiasis due to its importance in virulence, absence in the host and conservation among fungal pathogens. This dissertation is focused on the identification of inhibitors for this membrane enzyme. Cho1 has two substrates: cytidyldiphosphate-diacylglycerol (CDP-DAG) and serine. Previous studies identified a conserved CDP-alcohol phosphotransferase (CAPT) binding motif present within Cho1, and here we revealed that mutations in all but one conserved amino acid within the CAPT motif resulted in decreased Cho1. For serine, we have predicted a …
Biochemical And Kinetic Analysis Of Phosphofructokinase In The Eukaryotic Human Pathogen Entamoeba Histolytica, Jin Cho
All Dissertations
Entamoeba histolytica is a water- and food-borne intestinal parasite that causes amoebiasis and liver abscess in ~100 million people each year leading to ~100,000 deaths. This amitochondriate parasite lacks many metabolic pathways including the tricarboxylic acid cycle and oxidative phosphorylation, and cannot synthesize purines, pyrimidines, or most amino acids. As a result, E. histolytica is presumed to rely on its modified pyrophosphate (PPi)-dependent glycolytic pathway for ATP production during growth on glucose. This pathway relies on a PPi-dependent rather than ATP-dependent phosphofructokinase (PFK) and thus has a net production of three ATP per glucose. However, in …
Biochemical Analyses Of Udgx-A Crosslinking Uracil-Dna Glycosylase, Chuan Liang
Biochemical Analyses Of Udgx-A Crosslinking Uracil-Dna Glycosylase, Chuan Liang
All Dissertations
DNA base damage is common due to exposure to various endogenous and exogenous factors. To repair the base lesions, such as uracil from cytosine deamination, enzymes from the uracil-DNA glycosylase (UDG) superfamily are critical, which can recognize the damaged base and initiate the base excision repair (BER) pathway. There used to be six families of proteins identified in the UDG superfamily until a new member, UDGX, was found in Mycobacterium smegmatis, which is a unique DNA-crosslinking UDG. In this dissertation work, a series of biochemical analyses of the newly found UDGX are performed, including the analyses of structures, functions, …
Characterization Of The Effects Of The Pyrazolopyrimidine Inhibitor Grassofermata (Nav-2729) In The Eukaryotic Pathogen Trypanosoma Brucei, Kristina Marie Parman
Characterization Of The Effects Of The Pyrazolopyrimidine Inhibitor Grassofermata (Nav-2729) In The Eukaryotic Pathogen Trypanosoma Brucei, Kristina Marie Parman
All Dissertations
The protozoan pathogen, Trypanosoma brucei, is the causative agent of sleeping sickness in humans and nagana in livestock in sub-Saharan Africa. T. brucei cycles between tsetse fly and mammalian hosts, and it is adapted to survive in diverse host tissues. Variant Surface Glycoprotein (VSG) plays a key role in immune evasion in the mammalian host. The VSG membrane anchor requires two myristates, 14-carbon saturated fatty acids (FAs) that are scarce in the host. T. brucei can synthesize FAs de novo, but also readily takes up exogenous FAs, despite lacking homologs to fatty acid uptake proteins found in other …
A Cancer-Specific Study On The Differentially Expressed Protein-Protein Interactions Of Fumarate Hydratase, Sydney Lac
A Cancer-Specific Study On The Differentially Expressed Protein-Protein Interactions Of Fumarate Hydratase, Sydney Lac
Dissertations & Theses (Open Access)
Fumarate hydratase (FH) is an enzyme used in the Krebs Cycle to convert fumarate to malate, and it is controlled by the FH gene. In this paper, we will investigate its role in Uterine Corpus Endometrial Carcinoma (UCEC) and how FH-deficient cells affect tumorigenesis. It is well-established that FH has been extensively studied in connection with renal cell carcinoma, skin and uterine leiomyomas, pheochromocytoma, and paraganglioma. However, we aim to construct an interaction network of significant genes related to the FH gene under conditions of FH deficiency in the Kreb Cycle. Creating an interactive network that illustrates the interconnectedness of …